-LRB- CNN -RRB- -- It 's been described as one of the greatest Victorian gothic horror stories of all time . Two ships with 129 men on board and fitted with the latest technology , vanish with barely a trace left behind . One hundred and sixty years of searching -- one attempt as recent as last month -- have failed to find `` HMS Erebus '' and her sister ship , the somewhat appropriately named `` HMS Terror '' -- the two vessels lost in the Arctic .

In 1845 British Royal Navy captain Sir John Franklin set out with some of the finest sailors of the time on a mission to map the Northwest Passage . Franklin 's expedition was n't the first to the region , but it is the most infamous .

`` Why did this fail when all the others did n't , '' asks author William Battersby . `` There was something jinxed about the expedition . '' Battersby is one of many to be transfixed by the mystery of Franklin 's last voyage . `` We love adventure stories , of derring-do , win against all odds , but in this story they do n't and we still do n't know why . ''

The environment of the Northwest Passage is unforgiving . The landscape is vast and deserted , comparable only to Jupiter 's moons . The winters are unrelenting and bleak . Franklin 's men were faced with particularly brutally harsh temperatures and blizzards when they reached the region .

Despite the ships being reinforced with steel and holding three years worth or provisions , it appears the environment got the better of the crew . `` Man proposes , God disposes , '' says Bob Headland from the Scott Polar Research Institute , who regularly visits the region . ' `` And the ice gods are a fickle lot . ''

The disappearance of the Erebus and the Terror has prompted the longest search mission in history : Although there have been numerous attempts to find the ships , there has been no sign of them .

Ryan Harris from Parks Canada led the most recent mission to try to locate the shipwrecks . Last month , his crews spent hours scouring the ocean floor , searching waters up to 50 meters deep . `` It 's an incredible story . It 's got shipwrecks , the remoteness of the Arctic , putting the might of English industrialism against Mother Nature , '' says Harris .

Since 1997 Parks Canada has spent hundreds of thousands of dollars attempting to locate the `` Erebus '' and `` Terror . '' The tale of the Franklin expedition has enthralled Canadians -- the wreckage has the dubious honor of being the only national historic site in Canada that has n't been found yet .

`` Once Franklin received his orders that sealed his fate , '' Harris explains . `` In directing them south-west into ultimately the Victoria Strait it took them to the ice choke point . Once they fell into the clutch of that area , their fate was sealed . There 's not much wildlife there and it is isolated . ''

The last known account of the `` Erebus '' and `` Terror '' came in 1848 . A rock cairn with a message on it indicated that the harsh conditions had already claimed their first lives , with only 105 men left alive .

Franklin was one of the first casualties of his own expedition . That same year the men abandoned their ships , archaeologists believing they began making their way south in a desperate bid to find food .

However the harsh environment supported little , and with few animals to hunt and over 100 men to feed , the chance of survival was low . It 's been suggested that the men may have resorted to cannibalism in their last-ditch efforts to survive . `` There were far too many men to live off the environment . What man plans and what nature allows are two different things , '' says Headland .

Archaeologists have relied heavily upon oral Inuit history to try to put the pieces of the puzzle together . Based on their accounts it is thought some of the men lived for another three or four years after abandoning ship .

But questions remain over exactly what happened to them . In 160 years only two skeletons and three perfectly preserved bodies have been uncovered . It is likely diseases such as scurvy claimed many lives but Battersby believes it may have been the ships themselves that killed the sailors .

His theory is that the men succumbed to lead poisoning derived from the internal pipe system used to melt ice into drinking water . It 's hoped the discovery of the ships will provide answers .

' `` There 's a charm to the story , '' acknowledges Harris . `` By solving a mystery it takes the allure away . '' But having said that , Harris is determined the search will go on until the `` Erebus '' and the `` Terror '' are found . Parks Canada insists that their searches have not been futile and they 'll continue to gather information to help with future efforts . `` I hope we 're the last , '' says Harris .

But after 160 years it 's possible that this tale may be frozen in time forever . `` These are the last of the ghost ships , '' says Battersby . `` It is the world 's biggest ghost story . ''

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In 1845 Sir John Franklin and 129 men set out on a mission to map the Northwest Passage

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160 years of searching have failed to find the lost ships `` HMS Erebus '' and `` HMS Terror ''

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The last known account of the expedition was in 1848